Marinated Cucumber, Tomato & Onion Salad

This salad takes me back to my grandmother's kitchen every single time I make it. She'd slice everything paper-thin with this old mandoline that probably should have been thrown away years ago, then let it all marinate in this simple vinegar dressing that somehow transformed plain vegetables into something magical. The cucumbers stay crisp while absorbing all that tangy flavor, the tomatoes release their juices to make the dressing even better, and that sharp red onion mellows out into something sweet and perfect. It's one of those recipes that proves the best dishes are often the simplest ones.

My aunt brought this to our family reunion last summer, and it was the first bowl to empty even though there were fancy potato salads and elaborate sides everywhere. People kept asking what made it taste so good, and she'd just smile and say "time and good vinegar." My cousin's picky kids, who normally won't touch anything with onions, were eating it by the spoonful.

What You Need

• Fresh cucumbers - I like the regular ones better than English cucumbers for this because they have more texture
• Ripe tomatoes - Use the best ones you can find because their flavor really comes through in the marinade
• Red onion - Sweet onions work too, but red onion gives it that beautiful color and sharper bite
• Good vinegar - White vinegar works fine, but apple cider vinegar adds a little more complexity
• Simple seasonings - Just sugar, salt, pepper, and herbs to let the vegetables be the stars

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Step-by-Step Instructions

Vegetable Prep

Slice your cucumbers and onions as thin as you can manage - the thinner they are, the better they absorb the marinade. I use a sharp knife and take my time because even slices look better and marinate more evenly. Cut the tomatoes into wedges or thick slices, whatever you prefer, but try to keep the pieces substantial so they don't fall apart.

Marinade Creation

In a small bowl or jar, whisk together the vinegar, olive oil, sugar, salt, pepper, and whatever herbs you're using. The sugar is important because it balances the acidity of the vinegar and helps everything taste more rounded instead of just sharp and sour. Taste it and adjust - you might want more sugar or salt depending on your preferences.

Assembly Process

Put all your sliced vegetables in a large bowl and pour the marinade over everything. Toss it really well to make sure every piece gets coated with the dressing. The vegetables will look like too much for the amount of dressing, but trust the process - they'll release their own juices as they marinate.

Marinating Time

Cover the bowl and stick it in the fridge for at least an hour, though two hours is better and overnight is best. The vegetables will release their juices and mix with the marinade to create this incredibly flavorful dressing that's way better than what you started with.

Final Serving

Give everything a good stir before serving because the dressing settles. Use a slotted spoon to serve it so you don't get too much liquid on the plate, though some of that marinade is delicious for soaking up with bread.

I used to think the sugar was optional and made this without it a couple times. It was okay but had this harsh, one-dimensional taste that wasn't nearly as good. The sugar doesn't make it sweet, it just rounds out all the flavors and makes everything taste more complex and delicious.

Perfect Pairings

This is incredible alongside grilled meats, especially burgers and chicken, because the acidity cuts through rich flavors perfectly. It's also amazing with fried foods or anything heavy because it refreshes your palate between bites. At barbecues, I always put this out early because people like to snack on it while other things are cooking.

Creative Variations

Try adding some crumbled feta cheese just before serving for extra richness and salt. Fresh dill instead of oregano gives it a more cucumber-forward flavor that's really nice. Some people add bell peppers or radishes for extra crunch and color. I've also made this with different vinegars - red wine vinegar is really good, and rice vinegar makes it a bit milder.

Storage Solutions

This keeps in the fridge for about 3 days, though it's best within the first day or two. The vegetables start to get softer as time goes on, but some people actually prefer that texture. Never leave it out at room temperature for more than a couple hours because the marinade doesn't preserve it like you might think.

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This marinated cucumber, tomato, and onion salad has become my signature summer side dish because it's so simple but always gets rave reviews. It represents everything I love about cooking - taking basic ingredients and transforming them into something that tastes way more complex than the effort involved. Every time I make it, I'm reminded that sometimes the most memorable dishes are the ones that have been around forever for good reason.

Frequently Asked Questions

→ How long can this salad be stored?

This salad keeps well in the refrigerator for up to 3-4 days. The flavors actually improve with time, so it's great for meal prep!

→ Can I use different types of vinegar?

Yes! White vinegar and apple cider vinegar work best, but you can also try red wine vinegar or rice vinegar for different flavor profiles.

→ Should I peel the cucumbers?

It's up to your preference! Leaving the peel on adds color and nutrients, but you can peel them if you prefer a more tender texture.

→ Can I add other vegetables?

Absolutely! Bell peppers, radishes, or even corn kernels make great additions. Just make sure to slice everything thinly so it marinates well.

→ Why do I need to use a slotted spoon when serving?

The vegetables release juices as they marinate, creating excess liquid. A slotted spoon helps you serve the vegetables without too much of the accumulated liquid.